There are several requirements for telephone answering systems if the sytems are to operate properly and efficiently. A first requirement is that the system must distinguish between an incoming ring signal and outgoing dialing pulses from the telephone to which the system is connected. This discrimination must be such that the system will answer in the presence of an actual ring signal, but will not attempt to answer in the presence of outgoing dialing pulses.
Another requirement, if the telephone answering instrument is to operate efficiently, is that it should immediately stop operating and return to its original automatic answer positon should the calling party hang up before the end of the normal operational cycles of the instrument, or should the called party pick up before the end of the normal operational cycles, for the reasons set forth above.
The system of copending application Ser. No. 517,005 filed July 25, 1983 in the name of Bradford E. Hanscom, and assigned to the present assignee, provides a simple and economical means which fulfills all the foregoing requirements. The system of the present invention includes an additional feature which permits the called party to pick up and listen in to the message being recorded by the telephone answering system if he so desires. This gives the called party the opportunity to monitor the call and then decide whether or not he wishes to answer.